0000000000490507
AUTHOR
Ainhoa Genovés
Bax transmembrane domain interacts with prosurvival Bcl-2 proteins in biological membranes
The Bcl-2 (B-cell lymphoma 2) protein Bax (Bcl-2 associated X, apoptosis regulator) can commit cells to apoptosis via outer mitochondrial membrane permeabilization. Bax activity is controlled in healthy cells by prosurvival Bcl-2 proteins. C-terminal Bax transmembrane domain interactions were implicated recently in Bax pore formation. Here, we show that the isolated transmembrane domains of Bax, Bcl-xL (B-cell lymphoma-extra large), and Bcl-2 can mediate interactions between Bax and prosurvival proteins inside the membrane in the absence of apoptotic stimuli. Bcl-2 protein transmembrane domains specifically homooligomerize and heterooligomerize in bacterial and mitochondrial membranes. Thei…
Peptides Derived from the Transmembrane Domain of Bcl-2 Proteins as Potential Mitochondrial Priming Tools
The Bcl-2 family of proteins is crucial for apoptosis regulation. Members of this family insert through a specific C-terminal anchoring trans membrane domain (TMD) in the mitochondrial outer membrane where they hierarchically interact to determine cell fate. While the mitochondrial membrane has been proposed to actively participate in these protein protein interactions, the influence of the TMD in the membrane-mediated interaction is poorly understood. Synthetic peptides (TMD-pepts) corresponding to the putative TMD of antiapoptotic (Bcl-2, Bcl-xL, Bcl-w, and Mcl-1) and pro-apoptotic (Bax, Bak) members were synthesized and characterized. TMD-pepts bound more efficiently to mitochondria-like…
A multifunctional bicupin serves as precursor for a chromosomal protein of Pisum sativum seeds.
The fact that the psp54 gene codes for p16, a seed chromatin protein of Pisum sativum, has been described previously. In the present paper it is shown that p54, the p16 precursor, also exists as a free polypeptide in pea and that it also yields p38, a second polypeptide from the N-terminal region of p54, which is co-localized at a subcellular level with p16. By using antibodies against pea p16 and p38, it was found that these proteins are present in the members of the tribe Viciae examined. Sequence analysis and 3D modelling indicates that p54 proteins belong to the cupin superfamily, and that they are related to sucrose binding proteins and, to a lesser extent, to vicilin-type seed storage…
RNA-binding properties and membrane insertion of Melon necrotic spot virus (MNSV) double gene block movement proteins
AbstractAdvances in structural and biochemical properties of carmovirus movement proteins (MPs) have only been obtained in p7 and p9 from Carnation mottle virus (CarMV). Alignment of carmovirus MPs revealed a low conservation of amino acid identity but interestingly, similarity was elevated in regions associated with the functional secondary structure elements reported for CarMV which were conserved in all studied proteins. Nevertheless, some differential features in relation with CarMV MPs were identified in those from Melon necrotic virus (MNSV) (p7A and p7B). p7A was a soluble non-sequence specific RNA-binding protein, but unlike CarMV p7, its central region alone could not account for t…